My Rads don't turn off

[Kev432]

I have an open vented system with a wall mounted gas boiler with a storage tank upstairs(fully pumped). For the last month or so I have been coming in from work to find my living room at approx 31 degrees(phew!!) even though my stat is set to 22 degrees and is indicating the heating is off. I have changed the syncro motor on the mid position 3 way valve I have also changed the cylinder stat but the problem persists. For some reason when the room stat tells the heating system to turn off, the 3 way valve remains at the heating position and the pump keeps running until I manually turn the programmer on the boiler off, only then does the 3 way valve motor to the correct position. This happens almost every day. Please help

 

[B.O.B DOLE]

have you checked the room stat

 

[Kev432]

Yep, room stat is ok. It is a digital one and shows when its on and off. I can also hear it clicking when it turns on and off.

 

[doitall]

valve stays open because it's getting a live signal from somewhere, could this be a faulty programmer or the room stat wired up wrong.

 

[kevplumb]

could this be a faulty programmer

story of my life m8